Impact of Systolic Atrial Function on Atrial Natriuretic Factor During Rapid Atrial Pacing in a Canine Model

摘要

The aim of the study was to compare the influence of mechanical remodeling on the increase of atrial natriuretic factor (ANF). 8 dogs were subjected to rapid atrial pacing (RAP) at 400 bpm for 16 days. Left atrial systolic maximal dimension (LA-A) and left atrial appendage peak late emptying velocity (LAA-E) were assessed by echocardiography. Blood samples were taken from the right atrium and from the peripheral vein. All measurements were performed at baseline and after cessation of RAP. LA-A after RAP significantly enlarged and LAA-E velocities were significantly reduced compared with baseline values. RAP produced a significant elevation of ANF in a right atrial and in peripheral samples compared with baseline values. The change in plasma ANF correlated well with changes in LAA-E, but the correlation with LA-A was not significant. Our findings support the hypothesis that structural remodeling caused by RAP as a model of atrial fibrillation is a stimulus for release of ANF in the atria. In seems that atrial size and impaired systolic appendage function play an important role in secretion of ANF.